// NG2
import { Component, OnInit, EventEmitter, forwardRef, ElementRef, Input, Output } from '@angular/core';
import { NG_VALUE_ACCESSOR } from '@angular/forms';
// APP
import { OutsideClick } from '../../utils/outside-click/OutsideClick';
import { KeyCodes } from '../../utils/key-codes/KeyCodes';
import { Helpers } from '../../utils/Helpers';
import { NovoLabelService } from '../../services/novo-label-service';
// Vendor
import { ReplaySubject } from 'rxjs/ReplaySubject';

// Value accessor for the component (supports ngModel)
const CHIPS_VALUE_ACCESSOR = {
    provide: NG_VALUE_ACCESSOR,
    useExisting: forwardRef(() => NovoMultiPickerElement),
    multi: true
};

@Component({
    selector: 'multi-picker',
    providers: [CHIPS_VALUE_ACCESSOR],
    template: `
        <chip
            *ngFor="let item of _items | async | slice:0:chipsCount"
            [type]="type"
            [class.selected]="item == selected"
            (remove)="removeFromDisplay($event, item)"
            (select)="select($event, item)">
            {{ item.label }}
        </chip>
        <div *ngIf="items.length > chipsCount">
            <ul class="summary">
                <li *ngFor="let type of notShown">+ {{type.count}} {{ labels.more }} {{type.type}}</li>
            </ul>
        </div>
        <div class="chip-input-container">
            <novo-picker
                clearValueOnSelect="true"
                [config]="source"
                [placeholder]="placeholder"
                (select)="clickOption($event)"
                (keydown)="onKeyDown($event)"
                (focus)="onFocus($event)"
                (blur)="onTouched($event)"
                [overrideElement]="element">
            </novo-picker>
        </div>
        <i class="bhi-search" [class.has-value]="items.length"></i>
        <label class="clear-all" *ngIf="items.length" (click)="clearValue()">{{ labels.clearAll }} <i class="bhi-times"></i></label>
   `,
    host: {
        '[class.with-value]': 'items.length > 0'
    }
})
export class NovoMultiPickerElement implements OnInit {
    @Input() source: any;
    @Input() placeholder: any = '';
    @Input() types: any;
    @Output() changed: EventEmitter<any> = new EventEmitter();
    @Output() focus: EventEmitter<any> = new EventEmitter();
    @Output() blur: EventEmitter<any> = new EventEmitter();

    get value() {
        return this._value;
    }

    @Input()
    set value(selectedItems) {
        if (selectedItems) {
            this.types.forEach(x => this._value[x.value] = selectedItems[x.value]);
        } else {
            this._value = {};
            this.types.forEach(x => this._value[x.value] = []);
        }
        this.changed.emit(selectedItems);
        this.onModelChange(selectedItems);
    }

    items: any = [];
    _items = new ReplaySubject(1);
    options: any;
    _options: any;
    selected: any = null;
    config: any = {};
    chipsCount: number;
    selectAllOption: boolean;
    strictRelationship: boolean;
    // private data model
    _value: any = {};
    notShown: any = {};
    // Placeholders for the callbacks
    model: any;
    onModelChange: Function = () => {
    };
    onModelTouched: Function = () => {
    };

    constructor(public element: ElementRef, public labels: NovoLabelService) {
        this.chipsCount = 4;
    }

    ngOnInit() {
        this.selectAllOption = this.source.selectAllOption || false;
        this.chipsCount = this.source.chipsCount || 4;
        this.strictRelationship = this.source.strictRelationship || false;
        this.setupOptions();
    }

    clearValue() {
        this.types.forEach(type => this.modifyAllOfType(type.value, 'unselect'));
        this.items = [];
        this._items.next(this.items);
        this.value = this.setInitialValue(null);
        this.onModelChange(this.value);
    }

    removeFromDisplay(event, item) {
        this.remove(true, item);
        this.modifyAffectedParentsOrChildren(false, item);
    }

    setupOptions() {
        this.options = this.source.options || [];
        this._options = [];
        if (this.options) {
            this.options.forEach(option => {
                let formattedOption = this.setupOptionsByType(option);
                this._options.push(formattedOption);
            });
        }
        this.source.options = this._options;
    }

    setupOptionsByType(section) {
        let formattedSection: any = {
            type: section.type,
            label: section.label || section.type
        };
        formattedSection.data = section.data.map(item => {
            return this.formatOption(section, item);
        });
        if (this.selectAllOption) {
            let selectAll = this.createSelectAllOption(section);
            formattedSection.data.splice(0, 0, selectAll);
        }
        formattedSection.originalData = formattedSection.data.slice();
        return formattedSection;
    }

    formatOption(section, item) {
        let obj = {
            value: section.field ? item[section.field] : (item.value || item),
            label: section.format ? Helpers.interpolate(section.format, item) : item.label || String(item.value || item),
            type: section.type,
            checked: undefined,
            isParentOf: section.isParentOf,
            isChildOf: section.isChildOf
        };
        if (obj.isChildOf) {
            obj[section.isChildOf] = item[section.isChildOf];
        }
        return obj;
    }

    createSelectAllOption(section) {
        let selectAll = {
            value: 'ALL',
            label: `All ${section.type}`,
            type: section.type,
            checked: (this.model && this.model.length && (this.model.indexOf('ALL') !== -1)),
            isParentOf: section.isParentOf,
            isChildOf: section.isChildOf
        };
        if (section.isChildOf) {
            let allParents = section.data.reduce((accum, next) => {
                return accum.concat(next[section.isChildOf]);
            }, []);
            selectAll[section.isChildOf] = allParents;
        }
        return selectAll;
    }

    deselectAll() {
        this.selected = null;
    }

    select(event, item) {
        this.blur.emit(event);
        this.deselectAll();
        this.selected = item;
    }

    onFocus(e) {
        this.element.nativeElement.classList.add('selected');
        this.focus.emit(e);
    }

    clickOption(event) {
        if (event && !(event instanceof Event)) {
            if (event.checked === false) {
                this.remove(null, event);
            } else {
                this.add(event);
            }
            this.modifyAffectedParentsOrChildren(event.checked, event);
            // Set focus on the picker
            let input = this.element.nativeElement.querySelector('novo-picker > input');
            if (input) {
                input.focus();
            }
        }
    }

    add(event) {
        if (event.value === 'ALL') {
            this.modifyAllOfType(event.type, 'select');
        } else {
            this.updateDisplayItems(event, 'add');
            this.value[event.type].push(event.value);
            this.updateAllItemState(event.type);
            this.triggerValueUpdate();
        }
        this.updateParentOrChildren(event, 'select');
        this.select(null, event);
    }

    updateAllItemState(type) {
        let allOfType = this.getAllOfType(type);
        let allOfTypeSelected = this.allItemsSelected(allOfType, type);
        if (allOfTypeSelected) {
            this.selectAll(allOfType, type);
        }
        return { allOfType, allOfTypeSelected };
    }

    setIndeterminateState(allOfType, status) {
        if (!this.selectAllOption) { return; }
        let allItem = allOfType[0];
        allItem.indeterminate = status;
    }

    updateDisplayItems(item, action) {
        let adding = action === 'add';
        if (adding) {
            this.items.push(item);
        } else {
            if (this.items.indexOf(item) > -1) {
                this.items.splice(this.items.indexOf(item), 1);
            }
        }
        this.updateDisplayText(this.items);
        this._items.next(this.items);
    }

    updateDisplayText(items) {
        this.notShown = [];
        let notShown = items.slice(this.chipsCount);
        if (notShown.length > 0) {
            this.types.forEach(type => {
                let count;
                let selectedOfType = notShown.filter(x => x.type === type.value);
                if (selectedOfType.length === 1 && selectedOfType[0].value === 'ALL') {
                    count = this.getAllOfType(type.value).length - 1;
                } else {
                    count = selectedOfType.length;
                }
                let displayType = count === 1 ? type.singular : type.plural || type.value;
                if (count > 0) {
                    this.notShown.push({ type: displayType, count: count });
                }
            });
        }
    }

    remove(event, item) {
        let triggeredByEvent;
        if (event) {
            triggeredByEvent = true;
        }
        let itemToRemove = item;
        if (itemToRemove.value === 'ALL') {
            triggeredByEvent = false;
            this.modifyAllOfType(itemToRemove.type, 'unselect');
        } else if (this.allOfTypeSelected(itemToRemove.type)) {
            this.handleRemoveItemIfAllSelected(itemToRemove);
        }
        this.removeItem(item, triggeredByEvent);
    }

    removeItem(item, triggeredByEvent?: any) {
        item.checked = false;
        this.deselectAll();
        this.removeValue(item);
        if (item.value !== 'ALL') {
            this.updateParentOrChildren(item, 'unselect');
        }
        if (triggeredByEvent) {
            this.modifyAffectedParentsOrChildren(false, item);
        }
    }

    removeValue(item) {
        let updatedValues = this.value[item.type].filter(x => x !== item.value);
        this.value[item.type] = updatedValues;
        this.triggerValueUpdate();
        this.updateDisplayItems(item, 'remove');
    }

    onKeyDown(event) {
        if (event.keyCode === KeyCodes.BACKSPACE) {
            if (event.target && event.target.value.length === 0 && this.items.length) {
                if (event) {
                    event.stopPropagation();
                    event.preventDefault();
                }
                if (this.selected) {
                    this.remove(null, this.selected);
                } else {
                    this.select(event, this.items[this.items.length - 1]);
                }
            }
        }
    }

    allOfTypeSelected(type) {
        return this.items.filter(x => x.type === type && x.value === 'ALL').length > 0;
    }

    modifyAllOfType(type, action) {
        let selecting = action === 'select';
        let allOfType = this.getAllOfType(type);
        allOfType.forEach(item => {
            item.checked = selecting;
            item.indeterminate = false;
        });
        if (selecting) {
            this.selectAll(allOfType, type);
        } else {
            this.items = [...this.items.filter(x => x.type !== type)];
            this._items.next(this.items);
            this.value[type] = [];
        }
        if (this.selectAllOption) {
            this.updateAllParentsOrChildren(allOfType[0], action);
        }
        this.triggerValueUpdate();
    }

    triggerValueUpdate() {
        let updatedObject = {};
        this.types.forEach(x => updatedObject[x.value] = this.value[x.value]);
        this.value = updatedObject;
    }

    selectAll(allOfType, type) {
        if (!this.selectAllOption) { return; }
        allOfType[0].checked = true;
        let values = allOfType.map(i => {
            return i.value;
        });
        //remove 'ALL' value
        values.splice(0, 1);
        this.value[type] = values;
        let updatedItems = this.items.filter(x => x.type !== type);
        this.items = updatedItems;
        this.updateDisplayItems(allOfType[0], 'add');
    }

    handleRemoveItemIfAllSelected(item) {
        if (!this.selectAllOption) { return; }
        let type = item.type;
        let allOfType = this.getAllOfType(type);
        let allItem = allOfType[0];
        this.removeItem(allItem);
        allItem.indeterminate = true;
        let selectedItems = allOfType.filter(i => i.checked === true);
        this.items = [...this.items, ...selectedItems];
        let values = selectedItems.map(i => {
            return i.value;
        });
        this.value[type] = [...values];
    }

    handleOutsideClick(event) {
        // If the elements doesn't contain the target element, it is an outside click
        if (!this.element.nativeElement.contains(event.target)) {
            this.blur.emit(event);
            this.deselectAll();
        }
    }

    getAllOfType(type) {
        return this._options.filter(x => x.type === type)[0].originalData;
    }

    updateParentOrChildren(item, action) {
        if (this.strictRelationship && item.isParentOf) {
            this.updateChildrenValue(item, action);
        } else if (item.isChildOf && this.selectAllOption) {
            this.updateParentValue(item, action);
        }
    }

    modifyAffectedParentsOrChildren(selecting, itemChanged) {
        if (!itemChanged.isChildOf && !itemChanged.isParentOf) {
            return;
        }
        let parent = this.types.filter(x => !!x.isParentOf)[0];
        let parentType = parent.value;
        let allParentType = this.getAllOfType(parentType);
        let childType = allParentType[0].isParentOf;
        let allChildren = this.getAllOfType(childType);
        let allCheckedChildren = allChildren.filter(x => !!x.checked);

        allParentType.forEach(obj => {
            if (obj.value === 'ALL') {
                return;
            }
            let selectedChildrenOfParent = allCheckedChildren.filter(x => {
                return x[parentType].filter(y => y === obj.value).length > 0;
            });

            if (selecting) {
                if (obj.checked) { return; }
                obj.indeterminate = selectedChildrenOfParent.length > 0;
            } else {
                let allChildrenOfParent = allChildren.filter(x => {
                    return x.value !== 'ALL' && x[parentType].filter(y => y === obj.value).length > 0;
                });
                if (selectedChildrenOfParent.length > 0) {
                    if (obj.checked) {
                        if (this.strictRelationship && (allChildrenOfParent.length !== selectedChildrenOfParent.length)) {
                            obj.indeterminate = true;
                            obj.checked = false;
                            this.removeValue(obj);
                            this.addIndividualChildren(selectedChildrenOfParent);
                        }
                    } else {
                        obj.indeterminate = true;
                    }
                    if (this.strictRelationship && itemChanged.type !== parentType) {
                        if (obj.checked) {
                            obj.checked = false;
                            this.removeValue(obj);
                            this.addIndividualChildren(selectedChildrenOfParent);
                        }
                    }
                } else {
                    obj.indeterminate = false;
                    if (allChildrenOfParent.length === 0) {
                        //if it has no children and is checked, it should stay checked
                        return;
                    } else if (this.strictRelationship && itemChanged.type !== parentType) {
                        this.remove(null, obj);
                    }
                }
            }
        });
        if (this.selectAllOption) {
            this.updateIndeterminateStates(allParentType, allChildren, allCheckedChildren);
        }
    }

    updateAllParentsOrChildren(allItem, action) {
        if (allItem.isParentOf) {
            this.updateAllChildrenValue(allItem, action);
        } else if (allItem.isChildOf) {
            this.updateAllParentValue(allItem, action);
        }
    }

    updateAllChildrenValue(item, action) {
        let selecting = action === 'select';
        let childType = item.isParentOf;
        let potentialChildren = this.getAllOfType(childType);
        if (this.selectAllOption && this.allOfTypeSelected(childType) && !selecting) {
            this.remove(null, potentialChildren[0]);
            return;
        }
        potentialChildren.forEach(x => {
            if (x.value === 'ALL' && !x.checked) {
                if (selecting) {
                    x.checked = true;
                }
                x.indeterminate = selecting;
            } else {
                if (x.checked && !selecting) {
                    this.remove(null, x);
                }
                x.checked = selecting;
            }
        });
    }

    updateAllParentValue(item, action) {
        let selecting = action === 'select';
        let parentType = item.isChildOf;
        let potentialParents = this.getAllOfType(parentType);
        potentialParents.forEach(x => {
            if (!x.checked) {
                x.indeterminate = selecting;
            }
        });
    }

    updateIndeterminateStates(allParentType, allChildren, allCheckedChildren) {
        let allCheckedOrIndeterminateParents = allParentType.filter(x => (!!x.checked || !!x.indeterminate) && x.value !== 'ALL');
        let isParentIndeterminate = !!allParentType[0].checked ? false : allCheckedOrIndeterminateParents.length > 0;
        let isChildIndeterminate = !!allChildren[0].checked ? false : allCheckedChildren.length > 0;
        this.setIndeterminateState(allParentType, isParentIndeterminate);
        this.setIndeterminateState(allChildren, isChildIndeterminate);
    }

    updateChildrenValue(parent, action) {
        let selecting = action === 'select';
        let childType = parent.isParentOf;
        let potentialChildren = this.getAllOfType(childType);
        potentialChildren.forEach(x => {
            if (x.value === 'ALL') {
                return;
            }
            if (x[parent.type].filter(y => y === parent.value).length > 0) {
                if (x.checked && !selecting) {
                    x.checked = false;
                    if (this.allOfTypeSelected(childType)) {
                        this.handleRemoveItemIfAllSelected(x);
                    } else {
                        this.removeValue(x);
                    }
                }
                x.checked = selecting;
            }
        });
    }

    updateParentValue(child, action) {
        let allParentType = this.getAllOfType(child.isChildOf);
        if (allParentType[0].checked && action !== 'select') {
            this.handleRemoveItemIfAllSelected(allParentType[0]);
        }
    }

    addIndividualChildren(children) {
        let parentAlreadySelected = false;
        children.forEach(x => {
            if (x.isChildOf) { //only add children if their parents are not already selected
                x[x.isChildOf].forEach(parent => {
                    if (this.value[x.isChildOf].filter(p => p === parent).length > 0) {
                        parentAlreadySelected = true;
                    }
                });
            }
            if (this.value[x.type].filter(item => item === x.value).length === 0 && !parentAlreadySelected) {
                this.add(x);
            }
        });
    }

    setInitialValue(model) {
        this.items = [];
        this.value = model || {};
        if (!this.types) {
            return;
        }
        this.types.forEach(typeObj => {
            let type = typeObj.value;
            if (this.value[type]) {
                let indeterminateIsSet = false;
                let options = this.updateAllItemState(type);
                let optionsByType = options.allOfType;
                let allSelected = options.allOfTypeSelected;
                this.value[type].forEach(item => {
                    if (!allSelected && !indeterminateIsSet) {
                        indeterminateIsSet = true;
                        this.setIndeterminateState(optionsByType, true);
                    }
                    let value = optionsByType.filter(x => x.value === item)[0];
                    value.checked = true;
                    if (!allSelected) {
                        this.updateDisplayItems(value, 'add');
                    }
                    if (this.strictRelationship && value.isParentOf) {
                        this.updateChildrenValue(value, 'select');
                    }
                });
                if (typeObj.isChildOf) {
                    this.modifyAffectedParentsOrChildren(true, { value: type, isChildOf: true });
                }
            } else {
                this.value[type] = [];
            }
        });
    }

    allItemsSelected(optionsByType, type) {
        return this.value[type].length === optionsByType.length - 1;
    }

    // Set touched on blur
    onTouched(e) {
        this.element.nativeElement.classList.remove('selected');
        this.onModelTouched();
        this.blur.emit(e);
    }

    writeValue(model: any): void {
        this.model = model;
        this.setInitialValue(model);
    }

    registerOnChange(fn: Function): void {
        this.onModelChange = fn;
    }

    registerOnTouched(fn: Function): void {
        this.onModelTouched = fn;
    }
}